zero, first and second order
What zero, first and second order means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of zero, first and second order
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Reference: AQA
Zero order means concentration has no effect at all, first order means doubling concentration doubles the rate, and second order means doubling it quadruples the rate.
An unchanged rate when concentration doubles indicates zero order, a doubling of rate indicates first order, and a quadrupling of rate indicates second order.
Topics that use zero, first and second order
- Rate equations (A-level only) (AQA A-Level)
- How fast? (OCR A-Level)
Related terms
- Order of reaction
- Overall order
- Rate equation
- rate of reaction
- Rate-determining step
- units of k
- Calculating rate and concentration from the rate equation
- Colorimetry
Using zero, first and second order in the exam
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